Focused on transmission mechanisms of mineral rake reclaimer with high speed, heavy loads and frequently commutations, the design scheme of hydraulic system of “Constant pressure variable pump + Proportional directional valve + Double outlet pressure compensator” was proposed. The AMESim software was used to achieve the simulation of dynamic characteristics of the system. The results show that the designed hydraulic transmission system meets the design requirements, at the same time with minor hydraulic shocks under effect of large inertia loads. Moreover the system is running more smoothly with larger loads, which provides reference for the device modification of the similar hydraulic system.